Palynological dating of infra- and intertrappean sediments in the Mesozoic succession of Borehole PGD-6, Domra Sub-basin, West Bengal, India

Palynofloras have been examined from infra- and intertrappean sediments of the Panchet and Rajmahal Formations in the Domra Sub-basin of the Damodar Basin, West Bengal, India. Three distinct palynological assemblages are identified and referred to the following palynozones: (i)Lundbladispora–Verrucosisporites(506.60–505.00 m, late Early Triassic, (ii)Murospora florida(501.65–422.20 m. Late Jurassic, Kimmeridgian–Tithonian), and (iii)Cicatricosisporites australiensis(342.00–229.6 m. Early Cretaceous, Tithonian–Berriasian). The first occurrences ofCallialasporites turbatusandC. dampieriare at 501.65 m.Callialasporitesis a dominant element of the succeeding assemblages from the Panchet Formation and indicates a Jurassic age. The FAD ofCicatricosisporites australiensisandC. augustusat 342.00 m, and inconsistent occurrences ofAequitriradites spinulosus,Crybelosporites stylosusin the overlying sediments indicate Jurassic–Cretaceous transition.